Strobotac by General Radio Co., Cambridge, Massach

‘Strobotac’ stroboscope (type 631-B, serial no 2132) by General Radio Co., Cambridge, Massachusetts, 1935-1937. Used for early research on aircraft radar detection (c,1935), at the Royal Radar Establishment, Malvern and after 1946 at the Atomic Energy Research Establishment ,Harwell